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Comparing gvpe/src/connection.C (file contents):
Revision 1.49 by pcg, Sat Mar 12 18:10:40 2005 UTC vs.
Revision 1.100 by root, Wed Jul 17 05:34:17 2013 UTC

1/* 1/*
2 connection.C -- manage a single connection 2 connection.C -- manage a single connection
3 Copyright (C) 2003-2005 Marc Lehmann <gvpe@schmorp.de> 3 Copyright (C) 2003-2008,2010,2011,2013 Marc Lehmann <gvpe@schmorp.de>
4 4
5 This file is part of GVPE. 5 This file is part of GVPE.
6 6
7 GVPE is free software; you can redistribute it and/or modify 7 GVPE is free software; you can redistribute it and/or modify it
8 it under the terms of the GNU General Public License as published by 8 under the terms of the GNU General Public License as published by the
9 the Free Software Foundation; either version 2 of the License, or 9 Free Software Foundation; either version 3 of the License, or (at your
10 (at your option) any later version. 10 option) any later version.
11 11
12 This program is distributed in the hope that it will be useful, 12 This program is distributed in the hope that it will be useful, but
13 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
15 GNU General Public License for more details. 15 Public License for more details.
16 16
17 You should have received a copy of the GNU General Public License 17 You should have received a copy of the GNU General Public License along
18 along with gvpe; if not, write to the Free Software 18 with this program; if not, see <http://www.gnu.org/licenses/>.
19 Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19
20 Additional permission under GNU GPL version 3 section 7
21
22 If you modify this Program, or any covered work, by linking or
23 combining it with the OpenSSL project's OpenSSL library (or a modified
24 version of that library), containing parts covered by the terms of the
25 OpenSSL or SSLeay licenses, the licensors of this Program grant you
26 additional permission to convey the resulting work. Corresponding
27 Source for a non-source form of such a combination shall include the
28 source code for the parts of OpenSSL used as well as that of the
29 covered work.
20*/ 30*/
21 31
22#include "config.h" 32#include "config.h"
23 33
24#include <cassert>
25
26#include <list> 34#include <list>
35#include <queue>
36#include <utility>
27 37
28#include <openssl/rand.h> 38#include <openssl/rand.h>
29#include <openssl/evp.h> 39#include <openssl/evp.h>
30#include <openssl/rsa.h> 40#include <openssl/rsa.h>
31#include <openssl/err.h> 41#include <openssl/err.h>
32
33#include "gettext.h"
34 42
35#include "conf.h" 43#include "conf.h"
36#include "slog.h" 44#include "slog.h"
37#include "device.h" 45#include "device.h"
38#include "vpn.h" 46#include "vpn.h"
39#include "connection.h" 47#include "connection.h"
48#include "hkdf.h"
40 49
41#include "netcompat.h" 50#include "netcompat.h"
42 51
43#if !HAVE_RAND_PSEUDO_BYTES
44# define RAND_pseudo_bytes RAND_bytes
45#endif
46
47#define MAGIC "vped\xbd\xc6\xdb\x82" // 8 bytes of magic 52#define MAGIC "gvpe\xbd\xc6\xdb\x82" // 8 bytes of magic
48 53
49#define ULTRA_FAST 1 54#define ULTRA_FAST 1
50#define HLOG 15 55#define HLOG 15
51#include "lzf/lzf.h" 56#include "lzf/lzf.h"
52#include "lzf/lzf_c.c" 57#include "lzf/lzf_c.c"
53#include "lzf/lzf_d.c" 58#include "lzf/lzf_d.c"
54 59
60//////////////////////////////////////////////////////////////////////////////
61
62static std::queue< std::pair<run_script_cb *, const char *> > rs_queue;
63static ev::child rs_child_ev;
64
65namespace
66{
67 void // c++ requires external linkage here, apparently :(
68 rs_child_cb (ev::child &w, int revents)
69 {
70 w.stop ();
71
72 if (rs_queue.empty ())
73 return;
74
75 pid_t pid = run_script (*rs_queue.front ().first, false);
76 if (pid)
77 {
78 w.set (pid);
79 w.start ();
80 }
81 else
82 slog (L_WARN, rs_queue.front ().second);
83
84 delete rs_queue.front ().first;
85 rs_queue.pop ();
86 }
87};
88
89// despite the fancy name, this is quite a hack
90static void
91run_script_queued (run_script_cb *cb, const char *warnmsg)
92{
93 rs_queue.push (std::make_pair (cb, warnmsg));
94
95 if (!rs_child_ev.is_active ())
96 {
97 rs_child_ev.set<rs_child_cb> ();
98 rs_child_ev ();
99 }
100}
101
102//////////////////////////////////////////////////////////////////////////////
103
55struct crypto_ctx 104struct crypto_ctx
56{ 105{
57 EVP_CIPHER_CTX cctx; 106 EVP_CIPHER_CTX cctx;
58 HMAC_CTX hctx; 107 HMAC_CTX hctx;
59 108
60 crypto_ctx (const rsachallenge &challenge, int enc); 109 crypto_ctx (const auth_data &auth1, const auth_data &auth2, const ecdh_key &a, const ecdh_key &b, int enc);
61 ~crypto_ctx (); 110 ~crypto_ctx ();
62}; 111};
63 112
64crypto_ctx::crypto_ctx (const rsachallenge &challenge, int enc) 113crypto_ctx::crypto_ctx (const auth_data &auth1, const auth_data &auth2, const ecdh_key &a, const ecdh_key &b, int enc)
65{ 114{
115 ecdh_key s;
116
117 curve25519_combine (a, b, s);
118
119 {
120 u8 mac_key[MAC_KEYSIZE];
121 static const unsigned char mac_info[] = "gvpe mac key";
122
123 hkdf kdf (auth2.rsa.hkdf_salt, sizeof (auth2.rsa.hkdf_salt), HKDF_XTR_HASH ());
124 kdf.extract (auth2.rsa.ikm, sizeof (auth2.rsa.ikm));
125 kdf.extract (auth1.rsa.mac_key, sizeof (auth1.rsa.mac_key));
126 kdf.extract (s, sizeof (s));
127 kdf.extract_done (HKDF_PRF_HASH ());
128 kdf.expand (mac_key, sizeof (mac_key), mac_info, sizeof (mac_info));
129
130 HMAC_CTX_init (&hctx);
131 require (HMAC_Init_ex (&hctx, mac_key, MAC_KEYSIZE, MAC_DIGEST (), 0));
132 }
133
134 {
135 u8 cipher_key[CIPHER_KEYSIZE];
136 static const unsigned char cipher_info[] = "gvpe cipher key";
137
138 hkdf kdf (auth2.rsa.hkdf_salt, sizeof (auth2.rsa.hkdf_salt), HKDF_XTR_HASH ());
139 kdf.extract (auth2.rsa.ikm, sizeof (auth2.rsa.ikm));
140 kdf.extract (auth1.rsa.cipher_key, sizeof (auth1.rsa.cipher_key));
141 kdf.extract (s, sizeof (s));
142 kdf.extract_done (HKDF_PRF_HASH ());
143 kdf.expand (cipher_key, sizeof (cipher_key), cipher_info, sizeof (cipher_info));
144
66 EVP_CIPHER_CTX_init (&cctx); 145 EVP_CIPHER_CTX_init (&cctx);
67 require (EVP_CipherInit_ex (&cctx, CIPHER, 0, &challenge[CHG_CIPHER_KEY], 0, enc)); 146 require (EVP_CipherInit_ex (&cctx, CIPHER (), 0, cipher_key, 0, enc));
68 HMAC_CTX_init (&hctx); 147 }
69 HMAC_Init_ex (&hctx, &challenge[CHG_HMAC_KEY], HMAC_KEYLEN, DIGEST, 0);
70} 148}
71 149
72crypto_ctx::~crypto_ctx () 150crypto_ctx::~crypto_ctx ()
73{ 151{
74 require (EVP_CIPHER_CTX_cleanup (&cctx)); 152 require (EVP_CIPHER_CTX_cleanup (&cctx));
75 HMAC_CTX_cleanup (&hctx); 153 HMAC_CTX_cleanup (&hctx);
76} 154}
77 155
156static inline void
157auth_encrypt (RSA *key, const auth_data &auth, auth_encr &encr)
158{
159 if (RSA_public_encrypt (sizeof (auth.rsa),
160 (unsigned char *)&auth.rsa, (unsigned char *)&encr.rsa,
161 key, RSA_PKCS1_OAEP_PADDING) < 0)
162 fatal ("RSA_public_encrypt error");
163
164 memcpy (&encr.ecdh, &auth.ecdh, sizeof (encr.ecdh));
165}
166
167static inline bool
168auth_decrypt (RSA *key, const auth_encr &encr, auth_data &auth)
169{
170 u8 rsa_decrypt[RSA_KEYLEN];
171
172 if (RSA_private_decrypt (sizeof (encr.rsa),
173 (const unsigned char *)&encr.rsa, (unsigned char *)rsa_decrypt,
174 key, RSA_PKCS1_OAEP_PADDING) != sizeof (auth.rsa))
175 return 0;
176
177 memcpy (&auth.rsa, rsa_decrypt, sizeof (auth.rsa));
178 memcpy (&auth.ecdh, &encr.ecdh, sizeof (auth.ecdh));
179
180 return 1;
181}
182
78static void 183static void
79rsa_hash (const rsaid &id, const rsachallenge &chg, rsaresponse &h) 184auth_hash (const auth_data &auth, auth_mac &mac)
80{ 185{
81 EVP_MD_CTX ctx; 186 HMAC_CTX ctx;
82 187
83 EVP_MD_CTX_init (&ctx); 188 HMAC_CTX_init (&ctx);
84 require (EVP_DigestInit (&ctx, RSA_HASH)); 189 require (HMAC_Init_ex (&ctx, auth.rsa.auth_key, sizeof (auth.rsa.auth_key), AUTH_DIGEST (), 0));
85 require (EVP_DigestUpdate(&ctx, &chg, sizeof chg)); 190 require (HMAC_Update (&ctx, (const unsigned char *)&auth, sizeof auth));
86 require (EVP_DigestUpdate(&ctx, &id, sizeof id));
87 require (EVP_DigestFinal (&ctx, (unsigned char *)&h, 0)); 191 require (HMAC_Final (&ctx, (unsigned char *)&mac, 0));
88 EVP_MD_CTX_cleanup (&ctx); 192 HMAC_CTX_cleanup (&ctx);
89} 193}
90 194
91struct rsa_entry { 195void
92 tstamp expire; 196connection::generate_auth_data ()
93 rsaid id;
94 rsachallenge chg;
95};
96
97struct rsa_cache : list<rsa_entry>
98{ 197{
99 void cleaner_cb (time_watcher &w); time_watcher cleaner; 198 if (auth_expire < ev_now ())
100
101 bool find (const rsaid &id, rsachallenge &chg)
102 {
103 for (iterator i = begin (); i != end (); ++i)
104 {
105 if (!memcmp (&id, &i->id, sizeof id) && i->expire > NOW)
106 {
107 memcpy (&chg, &i->chg, sizeof chg);
108
109 erase (i);
110 return true;
111 }
112 }
113
114 if (cleaner.at < NOW)
115 cleaner.start (NOW + RSA_TTL);
116
117 return false;
118 }
119
120 void gen (rsaid &id, rsachallenge &chg)
121 {
122 rsa_entry e;
123
124 RAND_bytes ((unsigned char *)&id, sizeof id);
125 RAND_bytes ((unsigned char *)&chg, sizeof chg);
126
127 e.expire = NOW + RSA_TTL;
128 e.id = id;
129 memcpy (&e.chg, &chg, sizeof chg);
130
131 push_back (e);
132
133 if (cleaner.at < NOW)
134 cleaner.start (NOW + RSA_TTL);
135 }
136
137 rsa_cache ()
138 : cleaner (this, &rsa_cache::cleaner_cb)
139 { } 199 {
200 // request data
201 RAND_bytes ((unsigned char *)&snd_auth.rsa, sizeof snd_auth.rsa);
202 curve25519_generate (snd_ecdh_a, snd_auth.ecdh);
203 auth_hash (snd_auth, snd_auth_mac);
140 204
141} rsa_cache; 205 // eventual response data
142 206 curve25519_generate (rcv_ecdh_a, rcv_ecdh_b);
143void rsa_cache::cleaner_cb (time_watcher &w)
144{
145 if (!empty ())
146 { 207 }
147 w.start (NOW + RSA_TTL);
148 208
149 for (iterator i = begin (); i != end (); ) 209 // every use prolongs the expiry
150 if (i->expire <= NOW) 210 auth_expire = ev_now () + AUTH_TTL;
151 i = erase (i);
152 else
153 ++i;
154 }
155} 211}
156 212
157////////////////////////////////////////////////////////////////////////////// 213//////////////////////////////////////////////////////////////////////////////
158 214
159void pkt_queue::put (net_packet *p) 215pkt_queue::pkt_queue (double max_ttl, int max_queue)
216: max_ttl (max_ttl), max_queue (max_queue)
160{ 217{
161 if (queue[i]) 218 queue = new pkt [max_queue];
162 {
163 delete queue[i];
164 j = (j + 1) % QUEUEDEPTH;
165 }
166 219
167 queue[i] = p;
168
169 i = (i + 1) % QUEUEDEPTH;
170}
171
172net_packet *pkt_queue::get ()
173{
174 net_packet *p = queue[j];
175
176 if (p)
177 {
178 queue[j] = 0;
179 j = (j + 1) % QUEUEDEPTH;
180 }
181
182 return p;
183}
184
185pkt_queue::pkt_queue ()
186{
187 memset (queue, 0, sizeof (queue));
188 i = 0; 220 i = 0;
189 j = 0; 221 j = 0;
222
223 expire.set<pkt_queue, &pkt_queue::expire_cb> (this);
190} 224}
191 225
192pkt_queue::~pkt_queue () 226pkt_queue::~pkt_queue ()
193{ 227{
194 for (i = QUEUEDEPTH; --i > 0; ) 228 while (net_packet *p = get ())
229 delete p;
230
195 delete queue[i]; 231 delete [] queue;
196} 232}
197 233
234void
235pkt_queue::expire_cb (ev::timer &w, int revents)
236{
237 ev_tstamp expire = ev_now () - max_ttl;
238
239 for (;;)
240 {
241 if (empty ())
242 break;
243
244 double diff = queue[j].tstamp - expire;
245
246 if (diff >= 0.)
247 {
248 w.start (diff > 0.5 ? diff : 0.5);
249 break;
250 }
251
252 delete get ();
253 }
254}
255
256void
257pkt_queue::put (net_packet *p)
258{
259 ev_tstamp now = ev_now ();
260
261 // start expiry timer
262 if (empty ())
263 expire.start (max_ttl);
264
265 int ni = i + 1 == max_queue ? 0 : i + 1;
266
267 if (ni == j)
268 delete get ();
269
270 queue[i].pkt = p;
271 queue[i].tstamp = now;
272
273 i = ni;
274}
275
276net_packet *
277pkt_queue::get ()
278{
279 if (empty ())
280 return 0;
281
282 net_packet *p = queue[j].pkt;
283 queue[j].pkt = 0;
284
285 j = j + 1 == max_queue ? 0 : j + 1;
286
287 return p;
288}
289
198struct net_rateinfo { 290struct net_rateinfo
291{
199 u32 host; 292 u32 host;
200 double pcnt, diff; 293 double pcnt, diff;
201 tstamp last; 294 tstamp last;
202}; 295};
203 296
213 306
214 bool can (const sockinfo &si) { return can((u32)si.host); } 307 bool can (const sockinfo &si) { return can((u32)si.host); }
215 bool can (u32 host); 308 bool can (u32 host);
216}; 309};
217 310
218net_rate_limiter auth_rate_limiter, reset_rate_limiter; 311static net_rate_limiter auth_rate_limiter, reset_rate_limiter;
219 312
313bool
220bool net_rate_limiter::can (u32 host) 314net_rate_limiter::can (u32 host)
221{ 315{
222 iterator i; 316 iterator i;
223 317
224 for (i = begin (); i != end (); ) 318 for (i = begin (); i != end (); )
225 if (i->host == host) 319 if (i->host == host)
226 break; 320 break;
227 else if (i->last < NOW - NRL_EXPIRE) 321 else if (i->last < ev_now () - NRL_EXPIRE)
228 i = erase (i); 322 i = erase (i);
229 else 323 else
230 i++; 324 i++;
231 325
232 if (i == end ()) 326 if (i == end ())
234 net_rateinfo ri; 328 net_rateinfo ri;
235 329
236 ri.host = host; 330 ri.host = host;
237 ri.pcnt = 1.; 331 ri.pcnt = 1.;
238 ri.diff = NRL_MAXDIF; 332 ri.diff = NRL_MAXDIF;
239 ri.last = NOW; 333 ri.last = ev_now ();
240 334
241 push_front (ri); 335 push_front (ri);
242 336
243 return true; 337 return true;
244 } 338 }
246 { 340 {
247 net_rateinfo ri (*i); 341 net_rateinfo ri (*i);
248 erase (i); 342 erase (i);
249 343
250 ri.pcnt = ri.pcnt * NRL_ALPHA; 344 ri.pcnt = ri.pcnt * NRL_ALPHA;
251 ri.diff = ri.diff * NRL_ALPHA + (NOW - ri.last); 345 ri.diff = ri.diff * NRL_ALPHA + (ev_now () - ri.last);
252 346
253 ri.last = NOW; 347 ri.last = ev_now ();
254 348
255 double dif = ri.diff / ri.pcnt; 349 double dif = ri.diff / ri.pcnt;
256 350
257 bool send = dif > NRL_CUTOFF; 351 bool send = dif > NRL_CUTOFF;
258 352
272 366
273///////////////////////////////////////////////////////////////////////////// 367/////////////////////////////////////////////////////////////////////////////
274 368
275unsigned char hmac_packet::hmac_digest[EVP_MAX_MD_SIZE]; 369unsigned char hmac_packet::hmac_digest[EVP_MAX_MD_SIZE];
276 370
371void
277void hmac_packet::hmac_gen (crypto_ctx *ctx) 372hmac_packet::hmac_gen (crypto_ctx *ctx)
278{ 373{
279 unsigned int xlen; 374 unsigned int xlen;
280 375
281 HMAC_CTX *hctx = &ctx->hctx; 376 HMAC_CTX *hctx = &ctx->hctx;
282 377
283 HMAC_Init_ex (hctx, 0, 0, 0, 0); 378 require (HMAC_Init_ex (hctx, 0, 0, 0, 0));
284 HMAC_Update (hctx, ((unsigned char *) this) + sizeof (hmac_packet), 379 require (HMAC_Update (hctx, ((unsigned char *) this) + sizeof (hmac_packet),
285 len - sizeof (hmac_packet)); 380 len - sizeof (hmac_packet)));
286 HMAC_Final (hctx, (unsigned char *) &hmac_digest, &xlen); 381 require (HMAC_Final (hctx, (unsigned char *) &hmac_digest, &xlen));
287} 382}
288 383
289void 384void
290hmac_packet::hmac_set (crypto_ctx *ctx) 385hmac_packet::hmac_set (crypto_ctx *ctx)
291{ 386{
300 hmac_gen (ctx); 395 hmac_gen (ctx);
301 396
302 return !memcmp (hmac, hmac_digest, HMACLENGTH); 397 return !memcmp (hmac, hmac_digest, HMACLENGTH);
303} 398}
304 399
400void
305void vpn_packet::set_hdr (ptype type_, unsigned int dst) 401vpn_packet::set_hdr (ptype type_, unsigned int dst)
306{ 402{
307 type = type_; 403 type = type_;
308 404
309 int src = THISNODE->id; 405 int src = THISNODE->id;
310 406
315 411
316#define MAXVPNDATA (MAX_MTU - 6 - 6) 412#define MAXVPNDATA (MAX_MTU - 6 - 6)
317#define DATAHDR (sizeof (u32) + RAND_SIZE) 413#define DATAHDR (sizeof (u32) + RAND_SIZE)
318 414
319struct vpndata_packet : vpn_packet 415struct vpndata_packet : vpn_packet
416{
417 u8 data[MAXVPNDATA + DATAHDR]; // seqno
418
419 void setup (connection *conn, int dst, u8 *d, u32 len, u32 seqno);
420 tap_packet *unpack (connection *conn, u32 &seqno);
421
422private:
423 const u32 data_hdr_size () const
320 { 424 {
321 u8 data[MAXVPNDATA + DATAHDR]; // seqno
322
323 void setup (connection *conn, int dst, u8 *d, u32 len, u32 seqno);
324 tap_packet *unpack (connection *conn, u32 &seqno);
325private:
326
327 const u32 data_hdr_size () const
328 {
329 return sizeof (vpndata_packet) - sizeof (net_packet) - MAXVPNDATA - DATAHDR; 425 return sizeof (vpndata_packet) - sizeof (net_packet) - MAXVPNDATA - DATAHDR;
330 }
331 }; 426 }
427};
332 428
333void 429void
334vpndata_packet::setup (connection *conn, int dst, u8 *d, u32 l, u32 seqno) 430vpndata_packet::setup (connection *conn, int dst, u8 *d, u32 l, u32 seqno)
335{ 431{
336 EVP_CIPHER_CTX *cctx = &conn->octx->cctx; 432 EVP_CIPHER_CTX *cctx = &conn->octx->cctx;
338 ptype type = PT_DATA_UNCOMPRESSED; 434 ptype type = PT_DATA_UNCOMPRESSED;
339 435
340#if ENABLE_COMPRESSION 436#if ENABLE_COMPRESSION
341 u8 cdata[MAX_MTU]; 437 u8 cdata[MAX_MTU];
342 438
343 if (conn->features & ENABLE_COMPRESSION) 439 if (conn->features & FEATURE_COMPRESSION)
344 { 440 {
345 u32 cl = lzf_compress (d, l, cdata + 2, (l - 2) & ~7); 441 u32 cl = lzf_compress (d, l, cdata + 2, (l - 2) & ~7);
346 442
347 if (cl) 443 if (cl)
348 { 444 {
354 d[1] = cl; 450 d[1] = cl;
355 } 451 }
356 } 452 }
357#endif 453#endif
358 454
359 require (EVP_EncryptInit_ex (cctx, 0, 0, 0, 0)); 455 require (EVP_CipherInit_ex (cctx, 0, 0, 0, 0, 1));
360 456
361 struct { 457 struct {
362#if RAND_SIZE 458#if RAND_SIZE
363 u8 rnd[RAND_SIZE]; 459 u8 rnd[RAND_SIZE];
364#endif 460#endif
365 u32 seqno; 461 u32 seqno;
366 } datahdr; 462 } datahdr;
367 463
368 datahdr.seqno = ntohl (seqno); 464 datahdr.seqno = ntohl (seqno);
369#if RAND_SIZE 465#if RAND_SIZE
370 RAND_pseudo_bytes ((unsigned char *) datahdr.rnd, RAND_SIZE); 466 RAND_bytes ((unsigned char *) datahdr.rnd, RAND_SIZE);
371#endif 467#endif
372 468
373 require (EVP_EncryptUpdate (cctx, 469 require (EVP_EncryptUpdate (cctx,
374 (unsigned char *) data + outl, &outl2, 470 (unsigned char *) data + outl, &outl2,
375 (unsigned char *) &datahdr, DATAHDR)); 471 (unsigned char *) &datahdr, DATAHDR));
397 int outl = 0, outl2; 493 int outl = 0, outl2;
398 tap_packet *p = new tap_packet; 494 tap_packet *p = new tap_packet;
399 u8 *d; 495 u8 *d;
400 u32 l = len - data_hdr_size (); 496 u32 l = len - data_hdr_size ();
401 497
402 require (EVP_DecryptInit_ex (cctx, 0, 0, 0, 0)); 498 require (EVP_CipherInit_ex (cctx, 0, 0, 0, 0, 0));
403 499
404#if ENABLE_COMPRESSION 500#if ENABLE_COMPRESSION
405 u8 cdata[MAX_MTU]; 501 u8 cdata[MAX_MTU];
406 502
407 if (type == PT_DATA_COMPRESSED) 503 if (type == PT_DATA_COMPRESSED)
449 } 545 }
450}; 546};
451 547
452struct config_packet : vpn_packet 548struct config_packet : vpn_packet
453{ 549{
454 // actually, hmaclen cannot be checked because the hmac
455 // field comes before this data, so peers with other
456 // hmacs simply will not work.
457 u8 prot_major, prot_minor, randsize, hmaclen; 550 u8 prot_major, prot_minor, randsize;
458 u8 flags, challengelen, features, pad3; 551 u8 flags, features, pad6, pad7, pad8;
459 u32 cipher_nid, digest_nid, hmac_nid; 552 u32 cipher_nid, mac_nid, auth_nid;
460 553
461 void setup (ptype type, int dst); 554 void setup (ptype type, int dst);
462 bool chk_config () const; 555 bool chk_config () const;
463 556
464 static u8 get_features () 557 static u8 get_features ()
468 f |= FEATURE_COMPRESSION; 561 f |= FEATURE_COMPRESSION;
469#endif 562#endif
470#if ENABLE_ROHC 563#if ENABLE_ROHC
471 f |= FEATURE_ROHC; 564 f |= FEATURE_ROHC;
472#endif 565#endif
566#if ENABLE_BRIDGING
567 f |= FEATURE_BRIDGING;
568#endif
473 return f; 569 return f;
474 } 570 }
475}; 571};
476 572
573void
477void config_packet::setup (ptype type, int dst) 574config_packet::setup (ptype type, int dst)
478{ 575{
479 prot_major = PROTOCOL_MAJOR; 576 prot_major = PROTOCOL_MAJOR;
480 prot_minor = PROTOCOL_MINOR; 577 prot_minor = PROTOCOL_MINOR;
481 randsize = RAND_SIZE; 578 randsize = RAND_SIZE;
482 hmaclen = HMACLENGTH;
483 flags = 0; 579 flags = 0;
484 challengelen = sizeof (rsachallenge);
485 features = get_features (); 580 features = get_features ();
486 581
487 cipher_nid = htonl (EVP_CIPHER_nid (CIPHER)); 582 cipher_nid = htonl (EVP_CIPHER_nid (CIPHER ()));
488 digest_nid = htonl (EVP_MD_type (RSA_HASH));
489 hmac_nid = htonl (EVP_MD_type (DIGEST)); 583 mac_nid = htonl (EVP_MD_type (MAC_DIGEST ()));
584 auth_nid = htonl (EVP_MD_type (AUTH_DIGEST ()));
490 585
491 len = sizeof (*this) - sizeof (net_packet); 586 len = sizeof (*this) - sizeof (net_packet);
492 set_hdr (type, dst); 587 set_hdr (type, dst);
493} 588}
494 589
590bool
495bool config_packet::chk_config () const 591config_packet::chk_config () const
496{ 592{
497 if (prot_major != PROTOCOL_MAJOR) 593 if (prot_major != PROTOCOL_MAJOR)
498 slog (L_WARN, _("major version mismatch (remote %d <=> local %d)"), prot_major, PROTOCOL_MAJOR); 594 slog (L_WARN, _("major version mismatch (remote %d <=> local %d)"), prot_major, PROTOCOL_MAJOR);
499 else if (randsize != RAND_SIZE) 595 else if (randsize != RAND_SIZE)
500 slog (L_WARN, _("rand size mismatch (remote %d <=> local %d)"), randsize, RAND_SIZE); 596 slog (L_WARN, _("rand size mismatch (remote %d <=> local %d)"), randsize, RAND_SIZE);
501 else if (hmaclen != HMACLENGTH)
502 slog (L_WARN, _("hmac length mismatch (remote %d <=> local %d)"), hmaclen, HMACLENGTH);
503 else if (challengelen != sizeof (rsachallenge))
504 slog (L_WARN, _("challenge length mismatch (remote %d <=> local %d)"), challengelen, sizeof (rsachallenge));
505 else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER))) 597 else if (cipher_nid != htonl (EVP_CIPHER_nid (CIPHER ())))
506 slog (L_WARN, _("cipher mismatch (remote %x <=> local %x)"), ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER)); 598 slog (L_WARN, _("cipher algo mismatch (remote %x <=> local %x)"), ntohl (cipher_nid), EVP_CIPHER_nid (CIPHER ()));
507 else if (digest_nid != htonl (EVP_MD_type (RSA_HASH)))
508 slog (L_WARN, _("digest mismatch (remote %x <=> local %x)"), ntohl (digest_nid), EVP_MD_type (RSA_HASH));
509 else if (hmac_nid != htonl (EVP_MD_type (DIGEST))) 599 else if (mac_nid != htonl (EVP_MD_type (MAC_DIGEST ())))
510 slog (L_WARN, _("hmac mismatch (remote %x <=> local %x)"), ntohl (hmac_nid), EVP_MD_type (DIGEST)); 600 slog (L_WARN, _("mac algo mismatch (remote %x <=> local %x)"), ntohl (mac_nid), EVP_MD_type (MAC_DIGEST ()));
601 else if (auth_nid != htonl (EVP_MD_type (AUTH_DIGEST ())))
602 slog (L_WARN, _("auth algo mismatch (remote %x <=> local %x)"), ntohl (auth_nid), EVP_MD_type (AUTH_DIGEST ()));
511 else 603 else
512 return true; 604 return true;
513 605
514 return false; 606 return false;
515} 607}
516 608
517struct auth_req_packet : config_packet 609struct auth_req_packet : config_packet // UNPROTECTED
518{ 610{
519 char magic[8]; 611 char magic[8];
520 u8 initiate; // false if this is just an automatic reply 612 u8 initiate; // false if this is just an automatic reply
521 u8 protocols; // supported protocols (will be patched on forward) 613 u8 protocols; // supported protocols (will be patched on forward)
522 u8 pad2, pad3; 614 u8 pad2, pad3;
523 rsaid id; 615 auth_encr encr;
524 rsaencrdata encr;
525 616
526 auth_req_packet (int dst, bool initiate_, u8 protocols_) 617 auth_req_packet (int dst, bool initiate_, u8 protocols_)
527 { 618 {
528 config_packet::setup (PT_AUTH_REQ, dst); 619 config_packet::setup (PT_AUTH_REQ, dst);
529 strncpy (magic, MAGIC, 8); 620 memcpy (magic, MAGIC, 8);
530 initiate = !!initiate_; 621 initiate = !!initiate_;
531 protocols = protocols_; 622 protocols = protocols_;
532 623
533 len = sizeof (*this) - sizeof (net_packet); 624 len = sizeof (*this) - sizeof (net_packet);
534 } 625 }
535}; 626};
536 627
537struct auth_res_packet : config_packet 628struct auth_res_packet : config_packet // UNPROTECTED
538{ 629{
539 rsaid id;
540 u8 pad1, pad2, pad3;
541 u8 response_len; // encrypted length
542 rsaresponse response; 630 auth_response response;
543 631
544 auth_res_packet (int dst) 632 auth_res_packet (int dst)
545 { 633 {
546 config_packet::setup (PT_AUTH_RES, dst); 634 config_packet::setup (PT_AUTH_RES, dst);
547 635
581}; 669};
582 670
583///////////////////////////////////////////////////////////////////////////// 671/////////////////////////////////////////////////////////////////////////////
584 672
585void 673void
586connection::connection_established () 674connection::connection_established (const sockinfo &rsi)
587{ 675{
676 if (!have_snd_auth || !have_rcv_auth)
677 return;
678
679 si = rsi;
680 protocol = rsi.prot;
681
682 slog (L_INFO, _("%s(%s): connection established (%s), protocol version %d.%d."),
683 conf->nodename, (const char *)rsi,
684 is_direct ? "direct" : "forwarded",
685 PROTOCOL_MAJOR, prot_minor);
686
687 if (::conf.script_node_up)
688 {
689 run_script_cb *cb = new run_script_cb;
690 cb->set<connection, &connection::script_node_up> (this);
691 run_script_queued (cb, _("node-up command execution failed, continuing."));
692 }
693
694 delete ictx; ictx = new crypto_ctx (rcv_auth, snd_auth, rcv_ecdh_a, rcv_auth.ecdh, 0);
695 iseqno.reset (ntohl (rcv_auth.rsa.seqno) & 0x7fffffff);
696
697 delete octx; octx = new crypto_ctx (snd_auth, rcv_auth, snd_ecdh_a, snd_ecdh_b , 1);
698 oseqno = ntohl (snd_auth.rsa.seqno) & 0x7fffffff;
699
588 if (ictx && octx) 700 if (ictx && octx)
589 { 701 {
590 connectmode = conf->connectmode;
591
592 // make sure rekeying timeouts are slightly asymmetric 702 // make sure rekeying timeouts are slightly asymmetric
593 rekey.start (NOW + ::conf.rekey 703 ev::tstamp rekey_interval = ::conf.rekey + (conf->id > THISNODE->id ? 10 : 0);
594 + (conf->id > THISNODE->id ? 10 : 0)); 704 rekey.start (rekey_interval, rekey_interval);
705
595 keepalive.start (NOW + ::conf.keepalive); 706 keepalive.start (::conf.keepalive);
596 707
597 // send queued packets 708 // send queued packets
598 if (ictx && octx) 709 if (ictx && octx)
599 { 710 {
600 while (tap_packet *p = (tap_packet *)data_queue.get ()) 711 while (tap_packet *p = (tap_packet *)data_queue.get ())
601 { 712 {
602 send_data_packet (p); 713 if (p->len) send_data_packet (p);
603 delete p; 714 delete p;
604 } 715 }
605 716
606 while (vpn_packet *p = (vpn_packet *)vpn_queue.get ()) 717 while (vpn_packet *p = (vpn_packet *)vpn_queue.get ())
607 { 718 {
608 send_vpn_packet (p, si, IPTOS_RELIABILITY); 719 if (p->len) send_vpn_packet (p, si, IPTOS_RELIABILITY);
609 delete p; 720 delete p;
610 } 721 }
611 } 722 }
723
724 vpn->connection_established (this);
612 } 725 }
726#if 0
613 else 727 else
614 { 728 {
615 retry_cnt = 0; 729 retry_cnt = 0;
616 establish_connection.start (NOW + 5); 730 establish_connection.start (5);
617 keepalive.stop (); 731 keepalive.stop ();
618 rekey.stop (); 732 rekey.stop ();
619 } 733 }
734#endif
620} 735}
621 736
622void 737void
623connection::reset_si () 738connection::reset_si ()
624{ 739{
740 if (vpn->can_direct (THISNODE, conf))
625 protocol = best_protocol (THISNODE->protocols & conf->protocols); 741 protocol = best_protocol (THISNODE->protocols & conf->connectable_protocols ());
626 742 else
627 // mask out protocols we cannot establish 743 {
628 if (!conf->udp_port) protocol &= ~PROT_UDPv4; 744 slog (L_TRACE, _("%s: direct connection denied by config."), conf->nodename);
629 if (!conf->tcp_port) protocol &= ~PROT_TCPv4; 745 protocol = 0;
630 if (!conf->dns_port) protocol &= ~PROT_DNSv4; 746 }
631 747
632 si.set (conf, protocol); 748 si.set (conf, protocol);
749
750 is_direct = si.valid ();
633} 751}
634 752
635// ensure sockinfo is valid, forward if necessary 753// ensure sockinfo is valid, forward if necessary
636const sockinfo & 754const sockinfo &
637connection::forward_si (const sockinfo &si) const 755connection::forward_si (const sockinfo &si) const
638{ 756{
639 if (!si.valid ()) 757 if (!si.valid ())
640 { 758 {
641 connection *r = vpn->find_router (); 759 connection *r = vpn->find_router_for (this);
642 760
643 if (r) 761 if (r)
644 { 762 {
645 slog (L_DEBUG, _("%s: no common protocol, trying indirectly through %s (%s)"), 763 slog (L_DEBUG, _("%s: no common protocol, trying to route through %s."),
646 conf->nodename, r->conf->nodename, (const char *)r->si); 764 conf->nodename, r->conf->nodename);
647 return r->si; 765 return r->si;
648 } 766 }
649 else 767 else
650 slog (L_DEBUG, _("%s: node unreachable, no common protocol"), 768 slog (L_DEBUG, _("%s: node unreachable, no common protocol or no router available."),
651 conf->nodename); 769 conf->nodename);
652 } 770 }
653 771
654 return si; 772 return si;
655} 773}
665connection::send_ping (const sockinfo &si, u8 pong) 783connection::send_ping (const sockinfo &si, u8 pong)
666{ 784{
667 ping_packet *pkt = new ping_packet; 785 ping_packet *pkt = new ping_packet;
668 786
669 pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING); 787 pkt->setup (conf->id, pong ? ping_packet::PT_PONG : ping_packet::PT_PING);
788
789 slog (L_TRACE, "%s << %s [%s]", conf->nodename, pong ? "PT_PONG" : "PT_PING", (const char *)si);
670 send_vpn_packet (pkt, si, IPTOS_LOWDELAY); 790 send_vpn_packet (pkt, si, IPTOS_LOWDELAY);
671 791
672 delete pkt; 792 delete pkt;
673} 793}
674 794
689void 809void
690connection::send_auth_request (const sockinfo &si, bool initiate) 810connection::send_auth_request (const sockinfo &si, bool initiate)
691{ 811{
692 auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols); 812 auth_req_packet *pkt = new auth_req_packet (conf->id, initiate, THISNODE->protocols);
693 813
694 rsachallenge chg; 814 generate_auth_data ();
695 rsa_cache.gen (pkt->id, chg);
696 rsa_encrypt (conf->rsa_key, chg, pkt->encr); 815 auth_encrypt (conf->rsa_key, snd_auth, pkt->encr);
697 816
698 slog (L_TRACE, ">>%d PT_AUTH_REQ [%s]", conf->id, (const char *)si); 817 slog (L_TRACE, "%s << PT_AUTH_REQ [%s]", conf->nodename, (const char *)si);
699
700 send_vpn_packet (pkt, si, IPTOS_RELIABILITY | IPTOS_LOWDELAY); // rsa is very very costly 818 send_vpn_packet (pkt, si, IPTOS_RELIABILITY | IPTOS_LOWDELAY); // rsa is very very costly
701 819
702 delete pkt; 820 delete pkt;
703} 821}
704 822
705void 823void
706connection::send_auth_response (const sockinfo &si, const rsaid &id, const rsachallenge &chg) 824connection::send_auth_response (const sockinfo &si)
707{ 825{
708 auth_res_packet *pkt = new auth_res_packet (conf->id); 826 auth_res_packet *pkt = new auth_res_packet (conf->id);
709 827
710 pkt->id = id; 828 auth_hash (rcv_auth, pkt->response.mac);
829 memcpy (pkt->response.ecdh, rcv_ecdh_b, sizeof (rcv_ecdh_b));
711 830
712 rsa_hash (id, chg, pkt->response);
713
714 pkt->hmac_set (octx);
715
716 slog (L_TRACE, ">>%d PT_AUTH_RES [%s]", conf->id, (const char *)si); 831 slog (L_TRACE, "%s << PT_AUTH_RES [%s]", conf->nodename, (const char *)si);
717
718 send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly 832 send_vpn_packet (pkt, si, IPTOS_RELIABILITY); // rsa is very very costly
719 833
720 delete pkt; 834 delete pkt;
721} 835}
722 836
723void 837void
724connection::send_connect_info (int rid, const sockinfo &rsi, u8 rprotocols) 838connection::send_connect_info (int rid, const sockinfo &rsi, u8 rprotocols)
725{ 839{
726 slog (L_TRACE, ">>%d PT_CONNECT_INFO(%d,%s)\n", 840 slog (L_TRACE, "%s << PT_CONNECT_INFO(%s,%s,p%02x)", conf->nodename,
727 conf->id, rid, (const char *)rsi); 841 vpn->conns[rid - 1]->conf->nodename, (const char *)rsi,
842 conf->protocols);
728 843
729 connect_info_packet *r = new connect_info_packet (conf->id, rid, rsi, rprotocols); 844 connect_info_packet *r = new connect_info_packet (conf->id, rid, rsi, rprotocols);
730 845
731 r->hmac_set (octx); 846 r->hmac_set (octx);
732 send_vpn_packet (r, si); 847 send_vpn_packet (r, si);
733 848
734 delete r; 849 delete r;
735} 850}
736 851
737void 852inline void
738connection::establish_connection_cb (time_watcher &w) 853connection::establish_connection_cb (ev::timer &w, int revents)
739{ 854{
740 if (!ictx 855 if (!(ictx && octx)
741 && conf != THISNODE 856 && conf != THISNODE
742 && connectmode != conf_node::C_NEVER 857 && connectmode != conf_node::C_NEVER
743 && connectmode != conf_node::C_DISABLED 858 && connectmode != conf_node::C_DISABLED
744 && NOW > w.at) 859 && !w.is_active ())
745 { 860 {
746 w.at = TSTAMP_MAX; // first disable this watcher in case of recursion 861 // a bit hacky, if ondemand, and packets are no longer queued, then reset the connection
862 // and stop trying. should probably be handled by a per-connection expire handler.
863 if (connectmode == conf_node::C_ONDEMAND && vpn_queue.empty () && data_queue.empty ())
864 {
865 reset_connection ();
866 return;
867 }
747 868
748 double retry_int = double (retry_cnt & 3 869 last_establish_attempt = ev_now ();
870
871 ev::tstamp retry_int = ev::tstamp (retry_cnt & 3
749 ? (retry_cnt & 3) + 1 872 ? (retry_cnt & 3) + 1
750 : 1 << (retry_cnt >> 2)); 873 : 1 << (retry_cnt >> 2));
751 874
752 reset_si (); 875 reset_si ();
753 876
754 bool slow = si.prot & PROT_SLOW; 877 bool slow = si.prot & PROT_SLOW;
755 878
756 if (si.prot && !si.host) 879 if (si.prot && !si.host && vpn->can_direct (THISNODE, conf))
880 {
881 /*TODO*/ /* start the timer so we don't recurse endlessly */
882 w.start (1);
757 vpn->send_connect_request (conf->id); 883 vpn->send_connect_request (this);
884 }
758 else 885 else
759 { 886 {
887 if (si.valid ())
888 slog (L_DEBUG, _("%s: sending direct connection request to %s."),
889 conf->nodename, (const char *)si);
890
760 const sockinfo &dsi = forward_si (si); 891 const sockinfo &dsi = forward_si (si);
761 892
762 slow = slow || (dsi.prot & PROT_SLOW); 893 slow = slow || (dsi.prot & PROT_SLOW);
763 894
764 if (dsi.valid () && auth_rate_limiter.can (dsi)) 895 if (dsi.valid () && auth_rate_limiter.can (dsi))
768 else 899 else
769 send_ping (dsi, 0); 900 send_ping (dsi, 0);
770 } 901 }
771 } 902 }
772 903
773 retry_int *= slow ? 8. : 0.7; 904 retry_int *= slow ? 8. : 0.9;
774 905
775 if (retry_int < conf->max_retry) 906 if (retry_int < conf->max_retry)
776 retry_cnt++; 907 retry_cnt++;
777 else 908 else
778 retry_int = conf->max_retry; 909 retry_int = conf->max_retry;
779 910
780 w.start (NOW + retry_int); 911 w.start (retry_int);
781 } 912 }
782} 913}
783 914
784void 915void
785connection::reset_connection () 916connection::reset_connection ()
788 { 919 {
789 slog (L_INFO, _("%s(%s): connection lost"), 920 slog (L_INFO, _("%s(%s): connection lost"),
790 conf->nodename, (const char *)si); 921 conf->nodename, (const char *)si);
791 922
792 if (::conf.script_node_down) 923 if (::conf.script_node_down)
793 run_script (run_script_cb (this, &connection::script_node_down), false); 924 {
925 run_script_cb *cb = new run_script_cb;
926 cb->set<connection, &connection::script_node_down> (this);
927 run_script_queued (cb, _("node-down command execution failed, continuing."));
928 }
794 } 929 }
795 930
796 delete ictx; ictx = 0; 931 delete ictx; ictx = 0;
797 delete octx; octx = 0; 932 delete octx; octx = 0;
798#if ENABLE_DNS
799 dnsv4_reset_connection ();
800#endif
801 933
802 si.host = 0; 934 si.host = 0;
803 935
936 have_snd_auth = false;
937 have_rcv_auth = false;
938 auth_expire = 0.;
939
804 last_activity = 0; 940 last_activity = 0.;
941 //last_si_change = 0.;
805 retry_cnt = 0; 942 retry_cnt = 0;
806 943
807 rekey.stop (); 944 rekey.stop ();
808 keepalive.stop (); 945 keepalive.stop ();
809 establish_connection.stop (); 946 establish_connection.stop ();
816 send_reset (si); 953 send_reset (si);
817 954
818 reset_connection (); 955 reset_connection ();
819} 956}
820 957
821void 958// poor-man's rekeying
822connection::rekey_cb (time_watcher &w) 959inline void
960connection::rekey_cb (ev::timer &w, int revents)
823{ 961{
824 reset_connection (); 962 reset_connection ();
825 establish_connection (); 963 establish_connection ();
826} 964}
827 965
843 if (oseqno > MAX_SEQNO) 981 if (oseqno > MAX_SEQNO)
844 rekey (); 982 rekey ();
845} 983}
846 984
847void 985void
986connection::post_inject_queue ()
987{
988 // force a connection every now and when when packets are sent (max 1/s)
989 if (ev_now () - last_establish_attempt >= 0.95) // arbitrary
990 establish_connection.stop ();
991
992 establish_connection ();
993}
994
995void
848connection::inject_data_packet (tap_packet *pkt, bool broadcast/*TODO DDD*/) 996connection::inject_data_packet (tap_packet *pkt)
849{ 997{
850 if (ictx && octx) 998 if (ictx && octx)
851 send_data_packet (pkt); 999 send_data_packet (pkt);
852 else 1000 else
853 { 1001 {
854 if (!broadcast)//DDDD
855 data_queue.put (new tap_packet (*pkt)); 1002 data_queue.put (new tap_packet (*pkt));
856 1003 post_inject_queue ();
857 establish_connection ();
858 } 1004 }
859} 1005}
860 1006
1007void
861void connection::inject_vpn_packet (vpn_packet *pkt, int tos) 1008connection::inject_vpn_packet (vpn_packet *pkt, int tos)
862{ 1009{
863 if (ictx && octx) 1010 if (ictx && octx)
864 send_vpn_packet (pkt, si, tos); 1011 send_vpn_packet (pkt, si, tos);
865 else 1012 else
866 { 1013 {
867 vpn_queue.put ((vpn_packet *)new data_packet (*(data_packet *)pkt)); 1014 vpn_queue.put ((vpn_packet *)new data_packet (*(data_packet *)pkt));
868 1015 post_inject_queue ();
869 establish_connection ();
870 } 1016 }
871} 1017}
872 1018
873void 1019void
874connection::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi) 1020connection::recv_vpn_packet (vpn_packet *pkt, const sockinfo &rsi)
875{ 1021{
876 last_activity = NOW; 1022 last_activity = ev_now ();
877 1023
878 slog (L_NOISE, "<<%d received packet type %d from %d to %d", 1024 slog (L_NOISE, "%s >> received packet type %d from %d to %d.",
879 conf->id, pkt->typ (), pkt->src (), pkt->dst ()); 1025 conf->nodename, pkt->typ (), pkt->src (), pkt->dst ());
1026
1027 if (connectmode == conf_node::C_DISABLED)
1028 return;
880 1029
881 switch (pkt->typ ()) 1030 switch (pkt->typ ())
882 { 1031 {
883 case vpn_packet::PT_PING: 1032 case vpn_packet::PT_PING:
1033 slog (L_TRACE, "%s >> PT_PING", conf->nodename);
1034
884 // we send pings instead of auth packets after some retries, 1035 // we send pings instead of auth packets after some retries,
885 // so reset the retry counter and establish a connection 1036 // so reset the retry counter and establish a connection
886 // when we receive a ping. 1037 // when we receive a ping.
887 if (!ictx) 1038 if (!ictx)
888 { 1039 {
889 if (auth_rate_limiter.can (rsi)) 1040 if (auth_rate_limiter.can (rsi))
890 send_auth_request (rsi, true); 1041 send_auth_request (rsi, true);
891 } 1042 }
892 else 1043 else
1044 // we would love to change the socket address here, but ping's aren't
1045 // authenticated, so we best ignore it.
893 send_ping (rsi, 1); // pong 1046 send_ping (rsi, 1); // pong
894 1047
895 break; 1048 break;
896 1049
897 case vpn_packet::PT_PONG: 1050 case vpn_packet::PT_PONG:
1051 slog (L_TRACE, "%s >> PT_PONG", conf->nodename);
1052
1053 // a PONG might mean that the other side doesn't really know
1054 // about our desire for communication.
1055 establish_connection ();
898 break; 1056 break;
899 1057
900 case vpn_packet::PT_RESET: 1058 case vpn_packet::PT_RESET:
901 { 1059 {
902 reset_connection (); 1060 reset_connection ();
903 1061
904 config_packet *p = (config_packet *) pkt; 1062 config_packet *p = (config_packet *) pkt;
905 1063
906 if (!p->chk_config ()) 1064 if (!p->chk_config ())
907 { 1065 {
908 slog (L_WARN, _("%s(%s): protocol mismatch, disabling node"), 1066 slog (L_WARN, _("%s(%s): protocol mismatch, disabling node."),
909 conf->nodename, (const char *)rsi); 1067 conf->nodename, (const char *)rsi);
910 connectmode = conf_node::C_DISABLED; 1068 connectmode = conf_node::C_DISABLED;
911 } 1069 }
912 else if (connectmode == conf_node::C_ALWAYS) 1070 else if (connectmode == conf_node::C_ALWAYS)
913 establish_connection (); 1071 establish_connection ();
915 break; 1073 break;
916 1074
917 case vpn_packet::PT_AUTH_REQ: 1075 case vpn_packet::PT_AUTH_REQ:
918 if (auth_rate_limiter.can (rsi)) 1076 if (auth_rate_limiter.can (rsi))
919 { 1077 {
920 auth_req_packet *p = (auth_req_packet *) pkt; 1078 auth_req_packet *p = (auth_req_packet *)pkt;
921 1079
922 slog (L_TRACE, "<<%d PT_AUTH_REQ(%d)", conf->id, p->initiate); 1080 slog (L_TRACE, "%s >> PT_AUTH_REQ(%s,p%02x,f%02x)",
1081 conf->nodename, p->initiate ? "initiate" : "reply",
1082 p->protocols, p->features);
923 1083
924 if (p->chk_config () && !strncmp (p->magic, MAGIC, 8)) 1084 if (p->chk_config () && !memcmp (p->magic, MAGIC, 8))
925 { 1085 {
926 if (p->prot_minor != PROTOCOL_MINOR) 1086 if (p->prot_minor != PROTOCOL_MINOR)
927 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."), 1087 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."),
928 conf->nodename, (const char *)rsi, 1088 conf->nodename, (const char *)rsi,
929 PROTOCOL_MINOR, conf->nodename, p->prot_minor); 1089 PROTOCOL_MINOR, conf->nodename, p->prot_minor);
930 1090
931 if (p->initiate) 1091 if (p->initiate)
932 send_auth_request (rsi, false); 1092 send_auth_request (rsi, false);
933 1093
934 rsachallenge k; 1094 auth_data auth;
935 1095
936 if (!rsa_decrypt (::conf.rsa_key, p->encr, k)) 1096 if (!auth_decrypt (::conf.rsa_key, p->encr, auth))
937 { 1097 {
938 slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"), 1098 slog (L_ERR, _("%s(%s): challenge illegal or corrupted (%s). mismatched key or config file?"),
939 conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0)); 1099 conf->nodename, (const char *)rsi, ERR_error_string (ERR_get_error (), 0));
940 break;
941 } 1100 }
942 else 1101 else
943 { 1102 {
944 delete octx; 1103 bool chg = !have_rcv_auth || memcmp (&rcv_auth, &auth, sizeof auth);
945 1104
946 octx = new crypto_ctx (k, 1); 1105 rcv_auth = auth;
947 oseqno = ntohl (*(u32 *)&k[CHG_SEQNO]) & 0x7fffffff; 1106 have_rcv_auth = true;
948 1107
1108 send_auth_response (rsi);
1109
1110 if (chg)
1111 {
949 conf->protocols = p->protocols; 1112 conf->protocols = p->protocols;
950 features = p->features & config_packet::get_features (); 1113 features = p->features & config_packet::get_features ();
951 1114
952 send_auth_response (rsi, p->id, k);
953
954 connection_established (); 1115 connection_established (rsi);
955
956 break; 1116 }
957 } 1117 }
1118
1119 break;
958 } 1120 }
959 else 1121 else
960 slog (L_WARN, _("%s(%s): protocol mismatch"), 1122 slog (L_WARN, _("%s(%s): protocol mismatch."),
961 conf->nodename, (const char *)rsi); 1123 conf->nodename, (const char *)rsi);
962 1124
963 send_reset (rsi); 1125 send_reset (rsi);
964 } 1126 }
965 1127
966 break; 1128 break;
967 1129
968 case vpn_packet::PT_AUTH_RES: 1130 case vpn_packet::PT_AUTH_RES:
969 { 1131 {
970 auth_res_packet *p = (auth_res_packet *) pkt; 1132 auth_res_packet *p = (auth_res_packet *)pkt;
971 1133
972 slog (L_TRACE, "<<%d PT_AUTH_RES", conf->id); 1134 slog (L_TRACE, "%s >> PT_AUTH_RES", conf->nodename);
973 1135
974 if (p->chk_config ()) 1136 if (p->chk_config ())
975 { 1137 {
976 if (p->prot_minor != PROTOCOL_MINOR) 1138 if (memcmp (&p->response.mac, snd_auth_mac, sizeof (snd_auth_mac)))
977 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."),
978 conf->nodename, (const char *)rsi,
979 PROTOCOL_MINOR, conf->nodename, p->prot_minor);
980
981 rsachallenge chg;
982
983 if (!rsa_cache.find (p->id, chg))
984 { 1139 {
985 slog (L_ERR, _("%s(%s): unrequested auth response ignored"), 1140 slog (L_ERR, _("%s(%s): unrequested or outdated auth response, ignoring."),
986 conf->nodename, (const char *)rsi); 1141 conf->nodename, (const char *)rsi);
987 break;
988 } 1142 }
989 else 1143 else if (!have_snd_auth)
990 { 1144 {
991 crypto_ctx *cctx = new crypto_ctx (chg, 0); 1145 if (p->prot_minor != PROTOCOL_MINOR)
992 1146 slog (L_INFO, _("%s(%s): protocol minor version mismatch: ours is %d, %s's is %d."),
993 if (!p->hmac_chk (cctx))
994 {
995 slog (L_ERR, _("%s(%s): hmac authentication error on auth response, received invalid packet\n"
996 "could be an attack, or just corruption or a synchronization error"),
997 conf->nodename, (const char *)rsi); 1147 conf->nodename, (const char *)rsi,
998 break; 1148 PROTOCOL_MINOR, conf->nodename, p->prot_minor);
999 }
1000 else
1001 {
1002 rsaresponse h;
1003 1149
1004 rsa_hash (p->id, chg, h);
1005
1006 if (!memcmp ((u8 *)&h, (u8 *)p->response, sizeof h))
1007 {
1008 prot_minor = p->prot_minor; 1150 prot_minor = p->prot_minor;
1151 memcpy (snd_ecdh_b, p->response.ecdh, sizeof (snd_ecdh_b));
1009 1152
1010 delete ictx; ictx = cctx; 1153 have_snd_auth = true;
1011
1012 iseqno.reset (ntohl (*(u32 *)&chg[CHG_SEQNO]) & 0x7fffffff); // at least 2**31 sequence numbers are valid
1013
1014 si = rsi;
1015 protocol = rsi.prot;
1016
1017 connection_established (); 1154 connection_established (rsi);
1018
1019 slog (L_INFO, _("%s(%s): connection established, protocol version %d.%d"),
1020 conf->nodename, (const char *)rsi,
1021 p->prot_major, p->prot_minor);
1022
1023 if (::conf.script_node_up)
1024 run_script (run_script_cb (this, &connection::script_node_up), false);
1025
1026 break;
1027 }
1028 else
1029 slog (L_ERR, _("%s(%s): sent and received challenge do not match"),
1030 conf->nodename, (const char *)rsi);
1031 }
1032
1033 delete cctx;
1034 } 1155 }
1156
1157 break;
1035 } 1158 }
1036 } 1159 }
1037 1160
1038 send_reset (rsi); 1161 send_reset (rsi);
1039 break; 1162 break;
1050 { 1173 {
1051 vpndata_packet *p = (vpndata_packet *)pkt; 1174 vpndata_packet *p = (vpndata_packet *)pkt;
1052 1175
1053 if (!p->hmac_chk (ictx)) 1176 if (!p->hmac_chk (ictx))
1054 slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n" 1177 slog (L_ERR, _("%s(%s): hmac authentication error, received invalid packet\n"
1055 "could be an attack, or just corruption or a synchronization error"), 1178 "could be an attack, or just corruption or a synchronization error."),
1056 conf->nodename, (const char *)rsi); 1179 conf->nodename, (const char *)rsi);
1057 else 1180 else
1058 { 1181 {
1059 u32 seqno; 1182 u32 seqno;
1060 tap_packet *d = p->unpack (this, seqno); 1183 tap_packet *d = p->unpack (this, seqno);
1184 int seqclass = iseqno.seqno_classify (seqno);
1061 1185
1062 if (iseqno.recv_ok (seqno)) 1186 if (seqclass == 0) // ok
1063 { 1187 {
1064 vpn->tap->send (d); 1188 vpn->tap->send (d);
1065 1189
1066 if (si != rsi) 1190 if (si != rsi)
1067 { 1191 {
1068 // fast re-sync on connection changes, useful especially for tcp/ip 1192 // fast re-sync on source address changes, useful especially for tcp/ip
1193 //if (last_si_change < ev_now () + 5.)
1069 si = rsi; 1194 // {
1070
1071 slog (L_INFO, _("%s(%s): socket address changed to %s"), 1195 slog (L_INFO, _("%s(%s): changing socket address to %s."),
1072 conf->nodename, (const char *)si, (const char *)rsi); 1196 conf->nodename, (const char *)si, (const char *)rsi);
1197
1198 si = rsi;
1199
1200 if (::conf.script_node_change)
1201 {
1202 run_script_cb *cb = new run_script_cb;
1203 cb->set<connection, &connection::script_node_change> (this);
1204 run_script_queued (cb, _("node-change command execution failed, continuing."));
1205 }
1206
1207 // }
1208 //else
1209 // slog (L_INFO, _("%s(%s): accepted packet from %s, not (yet) redirecting traffic."),
1210 // conf->nodename, (const char *)si, (const char *)rsi);
1073 } 1211 }
1212 }
1213 else if (seqclass == 1) // far history
1214 slog (L_ERR, _("received very old packet (received %08lx, expected %08lx). "
1215 "possible replay attack, or just packet duplication/delay, ignoring."), seqno, iseqno.seq + 1);
1216 else if (seqclass == 2) // in-window duplicate, happens often on wireless
1217 slog (L_DEBUG, _("received recent duplicated packet (received %08lx, expected %08lx). "
1218 "possible replay attack, or just packet duplication, ignoring."), seqno, iseqno.seq + 1);
1219 else if (seqclass == 3) // reset
1220 {
1221 slog (L_ERR, _("received out-of-sync (far future) packet (received %08lx, expected %08lx). "
1222 "probably just massive packet loss, sending reset."), seqno, iseqno.seq + 1);
1223 send_reset (rsi);
1074 } 1224 }
1075 1225
1076 delete d; 1226 delete d;
1077 break; 1227 break;
1078 } 1228 }
1082 break; 1232 break;
1083 1233
1084 case vpn_packet::PT_CONNECT_REQ: 1234 case vpn_packet::PT_CONNECT_REQ:
1085 if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) 1235 if (ictx && octx && rsi == si && pkt->hmac_chk (ictx))
1086 { 1236 {
1087 connect_req_packet *p = (connect_req_packet *) pkt; 1237 connect_req_packet *p = (connect_req_packet *)pkt;
1088 1238
1089 assert (p->id > 0 && p->id <= vpn->conns.size ()); // hmac-auth does not mean we accept anything 1239 if (p->id > 0 && p->id <= vpn->conns.size ())
1090 connection *c = vpn->conns[p->id - 1];
1091 conf->protocols = p->protocols;
1092
1093 slog (L_TRACE, "<<%d PT_CONNECT_REQ(%d) [%d]\n",
1094 conf->id, p->id, c->ictx && c->octx);
1095
1096 if (c->ictx && c->octx)
1097 { 1240 {
1241 connection *c = vpn->conns[p->id - 1];
1242 conf->protocols = p->protocols;
1243
1244 slog (L_TRACE, "%s >> PT_CONNECT_REQ(%s,p%02x) [%d]",
1245 conf->nodename, vpn->conns[p->id - 1]->conf->nodename,
1246 p->protocols,
1247 c->ictx && c->octx);
1248
1249 if (c->ictx && c->octx)
1250 {
1098 // send connect_info packets to both sides, in case one is 1251 // send connect_info packets to both sides, in case one is
1099 // behind a nat firewall (or both ;) 1252 // behind a nat firewall (or both ;)
1100 c->send_connect_info (conf->id, si, conf->protocols); 1253 c->send_connect_info (conf->id, si, conf->protocols);
1101 send_connect_info (c->conf->id, c->si, c->conf->protocols); 1254 send_connect_info (c->conf->id, c->si, c->conf->protocols);
1255 }
1256 else
1257 c->establish_connection ();
1102 } 1258 }
1103 else 1259 else
1104 c->establish_connection (); 1260 slog (L_WARN,
1261 _("received authenticated connection request from unknown node #%d, config file mismatch?"),
1262 p->id);
1105 } 1263 }
1106 1264
1107 break; 1265 break;
1108 1266
1109 case vpn_packet::PT_CONNECT_INFO: 1267 case vpn_packet::PT_CONNECT_INFO:
1110 if (ictx && octx && rsi == si && pkt->hmac_chk (ictx)) 1268 if (ictx && octx && rsi == si && pkt->hmac_chk (ictx))
1111 { 1269 {
1112 connect_info_packet *p = (connect_info_packet *)pkt; 1270 connect_info_packet *p = (connect_info_packet *)pkt;
1113 1271
1114 if (p->id > 0 && p->id <= vpn->conns.size ()) // hmac-auth does not mean we accept anything 1272 if (p->id > 0 && p->id <= vpn->conns.size ())
1115 { 1273 {
1116 connection *c = vpn->conns[p->id - 1]; 1274 connection *c = vpn->conns[p->id - 1];
1117 1275
1118 c->conf->protocols = p->protocols; 1276 c->conf->protocols = p->protocols;
1119 protocol = best_protocol (c->conf->protocols & THISNODE->protocols & p->si.supported_protocols (c->conf)); 1277 protocol = best_protocol (c->conf->protocols & THISNODE->protocols & p->si.supported_protocols (c->conf));
1120 p->si.upgrade_protocol (protocol, c->conf); 1278 p->si.upgrade_protocol (protocol, c->conf);
1121 1279
1122 slog (L_TRACE, "<<%d PT_CONNECT_INFO(%d,%s) (%d)", 1280 slog (L_TRACE, "%s >> PT_CONNECT_INFO(%s,%s,protocols=%02x,protocol=%02x,upgradable=%02x) [%d]",
1123 conf->id, p->id, (const char *)p->si, !c->ictx && !c->octx); 1281 conf->nodename,
1282 vpn->conns[p->id - 1]->conf->nodename,
1283 (const char *)p->si,
1284 p->protocols,
1285 protocol,
1286 p->si.supported_protocols (c->conf),
1287 !c->ictx && !c->octx);
1124 1288
1125 const sockinfo &dsi = forward_si (p->si); 1289 const sockinfo &dsi = forward_si (p->si);
1126 1290
1127 if (dsi.valid ()) 1291 if (dsi.valid ())
1128 c->send_auth_request (dsi, true); 1292 c->send_auth_request (dsi, true);
1293 else
1294 slog (L_INFO, "connect info for %s received (%s), but still unable to contact.",
1295 vpn->conns[p->id - 1]->conf->nodename,
1296 (const char *)p->si);
1129 } 1297 }
1298 else
1299 slog (L_WARN,
1300 _("received authenticated connection request from unknown node #%d, config file mismatch?"),
1301 p->id);
1130 } 1302 }
1131 1303
1132 break; 1304 break;
1133 1305
1134 default: 1306 default:
1135 send_reset (rsi); 1307 send_reset (rsi);
1136 break; 1308 break;
1137 } 1309 }
1138} 1310}
1139 1311
1140void connection::keepalive_cb (time_watcher &w) 1312inline void
1313connection::keepalive_cb (ev::timer &w, int revents)
1141{ 1314{
1142 if (NOW >= last_activity + ::conf.keepalive + 30) 1315 ev_tstamp when = last_activity + ::conf.keepalive - ev::now ();
1316
1317 if (when >= 0)
1318 w.start (when);
1319 else if (when < -15)
1143 { 1320 {
1144 reset_connection (); 1321 reset_connection ();
1145 establish_connection (); 1322 establish_connection ();
1146 } 1323 }
1147 else if (NOW < last_activity + ::conf.keepalive)
1148 w.start (last_activity + ::conf.keepalive);
1149 else if (conf->connectmode != conf_node::C_ONDEMAND 1324 else if (conf->connectmode != conf_node::C_ONDEMAND
1150 || THISNODE->connectmode != conf_node::C_ONDEMAND) 1325 || THISNODE->connectmode != conf_node::C_ONDEMAND)
1151 { 1326 {
1327 w.start (3);
1152 send_ping (si); 1328 send_ping (si);
1153 w.start (NOW + 5);
1154 } 1329 }
1155 else if (NOW < last_activity + ::conf.keepalive + 10) 1330 else if (when >= -10)
1156 // hold ondemand connections implicitly a few seconds longer 1331 // hold ondemand connections implicitly a few seconds longer
1157 // should delete octx, though, or something like that ;) 1332 // should delete octx, though, or something like that ;)
1158 w.start (last_activity + ::conf.keepalive + 10); 1333 w.start (when + 10);
1159 else 1334 else
1160 reset_connection (); 1335 reset_connection ();
1161} 1336}
1162 1337
1338void
1163void connection::send_connect_request (int id) 1339connection::send_connect_request (int id)
1164{ 1340{
1165 connect_req_packet *p = new connect_req_packet (conf->id, id, conf->protocols); 1341 connect_req_packet *p = new connect_req_packet (conf->id, id, THISNODE->protocols);
1166 1342
1167 slog (L_TRACE, ">>%d PT_CONNECT_REQ(%d)", conf->id, id); 1343 slog (L_TRACE, "%s << PT_CONNECT_REQ(%s,p%02x)",
1344 conf->nodename, vpn->conns[id - 1]->conf->nodename,
1345 THISNODE->protocols);
1168 p->hmac_set (octx); 1346 p->hmac_set (octx);
1169 send_vpn_packet (p, si); 1347 send_vpn_packet (p, si);
1170 1348
1171 delete p; 1349 delete p;
1172} 1350}
1173 1351
1174void connection::script_node () 1352void
1353connection::script_init_env (const char *ext)
1175{ 1354{
1176 vpn->script_if_up ();
1177
1178 char *env; 1355 char *env;
1356 asprintf (&env, "IFUPDATA%s=%s", ext, conf->if_up_data); putenv (env);
1357 asprintf (&env, "NODENAME%s=%s", ext, conf->nodename); putenv (env);
1358 asprintf (&env, "MAC%s=%02x:%02x:%02x:%02x:%02x:%02x", ext,
1359 0xfe, 0xfd, 0x80, 0x00, conf->id >> 8,
1360 conf->id & 0xff); putenv (env);
1361}
1362
1363void
1364connection::script_init_connect_env ()
1365{
1366 vpn->script_init_env ();
1367
1368 char *env;
1179 asprintf (&env, "DESTID=%d", conf->id); putenv (env); 1369 asprintf (&env, "DESTID=%d", conf->id); putenv (env);
1370 asprintf (&env, "DESTSI=%s", (const char *)si); putenv (env);
1180 asprintf (&env, "DESTNODE=%s", conf->nodename); putenv (env); 1371 asprintf (&env, "DESTNODE=%s", conf->nodename); putenv (env);
1181 asprintf (&env, "DESTIP=%s", si.ntoa ()); putenv (env); 1372 asprintf (&env, "DESTIP=%s", si.ntoa ()); putenv (env);
1182 asprintf (&env, "DESTPORT=%d", ntohs (si.port)); putenv (env); 1373 asprintf (&env, "DESTPORT=%d", ntohs (si.port)); putenv (env);
1183} 1374}
1184 1375
1376inline const char *
1185const char *connection::script_node_up () 1377connection::script_node_up ()
1186{ 1378{
1187 script_node (); 1379 script_init_connect_env ();
1188 1380
1189 putenv ("STATE=up"); 1381 putenv ((char *)"STATE=up");
1190 1382
1383 char *filename;
1384 asprintf (&filename,
1385 "%s/%s",
1386 confbase,
1191 return ::conf.script_node_up ? ::conf.script_node_up : "node-up"; 1387 ::conf.script_node_up ? ::conf.script_node_up : "node-up");
1192}
1193 1388
1389 return filename;
1390}
1391
1392inline const char *
1393connection::script_node_change ()
1394{
1395 script_init_connect_env ();
1396
1397 putenv ((char *)"STATE=change");
1398
1399 char *filename;
1400 asprintf (&filename,
1401 "%s/%s",
1402 confbase,
1403 ::conf.script_node_change ? ::conf.script_node_change : "node-change");
1404
1405 return filename;
1406}
1407
1408inline const char *
1194const char *connection::script_node_down () 1409connection::script_node_down ()
1195{ 1410{
1196 script_node (); 1411 script_init_connect_env ();
1197 1412
1198 putenv ("STATE=down"); 1413 putenv ((char *)"STATE=down");
1199 1414
1200 return ::conf.script_node_up ? ::conf.script_node_down : "node-down"; 1415 char *filename;
1416 asprintf (&filename,
1417 "%s/%s",
1418 confbase,
1419 ::conf.script_node_down ? ::conf.script_node_down : "node-down");
1420
1421 return filename;
1201} 1422}
1202 1423
1203connection::connection (struct vpn *vpn, conf_node *conf) 1424connection::connection (struct vpn *vpn, conf_node *conf)
1204: vpn(vpn), conf(conf) 1425: vpn(vpn), conf(conf),
1205, rekey (this, &connection::rekey_cb)
1206, keepalive (this, &connection::keepalive_cb)
1207, establish_connection (this, &connection::establish_connection_cb)
1208#if ENABLE_DNS 1426#if ENABLE_DNS
1209, dns (0) 1427 dns (0),
1210#endif 1428#endif
1429 data_queue(conf->max_ttl, conf->max_queue + 1),
1430 vpn_queue(conf->max_ttl, conf->max_queue + 1)
1211{ 1431{
1432 rekey .set<connection, &connection::rekey_cb > (this);
1433 keepalive .set<connection, &connection::keepalive_cb > (this);
1434 establish_connection.set<connection, &connection::establish_connection_cb> (this);
1435
1436 last_establish_attempt = 0.;
1212 octx = ictx = 0; 1437 octx = ictx = 0;
1213 retry_cnt = 0;
1214 1438
1215 if (!conf->protocols) // make sure some protocol is enabled 1439 connectmode = conf->connectmode;
1216 conf->protocols = PROT_UDPv4;
1217 1440
1218 connectmode = conf_node::C_ALWAYS; // initial setting 1441 // queue a dummy packet to force an initial connection attempt
1442 if (connectmode != conf_node::C_ALWAYS && connectmode != conf_node::C_DISABLED)
1443 vpn_queue.put (new net_packet);
1444
1219 reset_connection (); 1445 reset_connection ();
1220} 1446}
1221 1447
1222connection::~connection () 1448connection::~connection ()
1223{ 1449{
1224 shutdown (); 1450 shutdown ();
1225} 1451}
1226 1452
1453void
1227void connection_init () 1454connection_init ()
1228{ 1455{
1229 auth_rate_limiter.clear (); 1456 auth_rate_limiter.clear ();
1230 reset_rate_limiter.clear (); 1457 reset_rate_limiter.clear ();
1231} 1458}
1232 1459

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